I am going to be honest, and strait forward with you. I am NOT being mean don't mis read me. To be honest that is a poor group for 50 yards. If that was 100 yards I would say you can tweek it and do better. At 150 yards I would say you got a shooter. Those three that are touching would be a good group at 100 yards.
I have seen sub 1" groups at 50 yards not even be in the same zip code at 100, and I have seen 1" groups at 100 yards not even touch paper at 150.
Again I am not trying to be mean but I think the hard lead is going to cause more troubles than it is worth. I have been down your road I have fired a small fortune worth of powder and bullets doing what you are doing. The only hard lead bullets I got to shoot half way good was the Lyman whitworth bullet. Loading this bullet was tough, but it shot well.
Again I think that you should look into paper patching your bullets with soft lead. Use a felt wad between the powder and bullet. SIze your patched bullets dry with a Lee sizer so your paper stayes dry. Only lube before you shoot them.
I think you will see your groups shape up. Also I didn't get real good groups until I backed the powder off. I am using 80 gr of Pyrodex P, 386 gr Lee 459-405-HB, and a CCI mag cap.
In this picture, I shot two groups. Both were shot at 100 yards. The purpose of this was to show the difference that paper patches make in my rifle. I did clean between groups, but NOT between shots.
I am not going to say that by shooting paper patch you will get sub 1" groups every time, but it helps. I have shot MANY sub 1" groups with this rifle, but I would say that day in and day out it will be sub 2" at 100 yards about any time.
If you have your heart set on shooting HARD lead good luck. :hatsoff: Ron